Radiation imaging device

ABSTRACT

A radiation imaging device according to one embodiment comprises a radiation detection panel, a base substrate having a support surface configured to support the radiation detection panel, and a housing, wherein: the housing has a top wall and a bottom wall, the base substrate has a protruding portion which protrudes further outward than the radiation detection panel when seen in a direction orthogonal to the support surface, a first extending portion is provided to the support surface of the protruding portion, a second extending portion is provided to a back surface of the protruding portion, the second extending portion being disposed at a position which it faces the first extending portion with the protruding portion interposed therebetween, and the base substrate is supported on the top wall via the first extending portion and is supported on the bottom wall via the second extending portion.

TECHNICAL FIELD

The disclosure relates to a radiation imaging device.

BACKGROUND ART

Patent Document 1 describes an X-ray detection device. This X-raydetection device includes a support member fixed in a housing (anenvelope) and an X-ray detection panel fixed on the support member.

CITATION LIST Patent Document

-   [Patent Document 1] Japanese Unexamined Patent Publication No.    2010-145349

SUMMARY OF INVENTION Technical Problem

In the configuration in which the X-ray detection panel is supported inthe housing via the support member as described above, it is required tostably support the support member in the housing. On the other hand,Patent Document 1 does not describe a specific structure which fixes thesupport member in the housing.

One aspect of the disclosure is to provide a radiation imaging devicecapable of stably supporting a base substrate on which a radiationdetection panel is supported.

Solution to Problem

A radiation imaging device according to an aspect of the disclosureincludes a radiation detection panel having a first surface on which adetection region for detecting radiation is formed and a second surfaceon a side opposite to the first surface, a base substrate having asupport surface configured to face the second surface of the radiationdetection panel and configured to support the radiation detection panel,and a housing configured to accommodate the radiation detection paneland the base substrate, wherein the housing has a first wall portionwhich faces the first surface and a second wall portion which faces thesecond surface, the base substrate has a protruding portion whichprotrudes further outward than the radiation detection panel when seenin a first direction orthogonal to the support surface, a firstextending portion configured to extend in the first direction isprovided on the support surface of the protruding portion, a secondextending portion disposed at a position at which the second extendingportion faces the first extending portion with the protruding portioninterposed therebetween and configured to extend in the first directionis provided on a surface of the protruding portion on a side opposite tothe support surface, and the base substrate is supported on the firstwall portion via the first extending portion and is supported on thesecond wall portion via the second extending portion.

According to the radiation imaging device, the base substrate (theprotruding portion) is sandwiched by parts of the housing (the firstwall portion and the second wall portion) which face each other via thefirst extending portion and the second extending portion. Thus, the basesubstrate can be stably supported with respect to the housing. Here, asa method of supporting the base substrate with respect to the housing,for example, there is a method of supporting a back surface of the basesubstrate (a surface opposite to the support surface) on the second wallportion via a columnar support member. According to the radiationimaging device, since the base substrate is supported on the housing viathe first extending portion and the second extending portion, even whenthe above-described supporting method is used in combination, the numberof support members provided on the back surface of the base substratecan be reduced. Thus, it is possible to make it difficult for an impactfrom the outside (particularly, the second wall portion) to betransmitted to the back surface of the base substrate. As a result, itis possible to reduce the impact on the radiation detection paneldisposed on the base substrate.

The first extending portion may be a positioning member which positionsthe radiation detection panel. With such a configuration, since thefirst extending portion makes it possible to easily position theradiation detection panel with respect to the support surface of thebase substrate, assembly workability can be improved.

The first extending portion and the second extending portion may beformed separately from the base substrate. With such a configuration,warpage of the base substrate can be reduced as compared with a case inwhich the base substrate is integrally formed with at least one of thefirst extending portion and the second extending portion.

The first extending portion and the second extending portion may bemounted on the protruding portion by a common mounting member. With sucha configuration, a relative positional relationship between the firstextending portion and the second extending portion can be maintainedwith high accuracy, and the base substrate can be supported more stably.

The second extending portion may be larger than the first extendingportion when seen in the first direction, and the second extendingportion may have a portion which does not overlap the first extendingportion when seen in the first direction. The second wall portion of thehousing located on the side opposite to the first surface on which thedetection region of the radiation detection panel is formed (that is,facing the second surface) is usually a ground surface (a bottom wall).Therefore, with such a configuration, the base substrate can besupported more stably by making the second extending portion supportedby the second wall portion larger than the first extending portion.Further, since an impact from the ground surface side (the second wallportion) can be appropriately absorbed by the second extending portion,it is possible to make it difficult for the impact to be transmitted tothe radiation detection panel.

A plurality of first extending portions disposed apart from each othermay be provided, and a plurality of second extending portions disposedapart from each other to correspond to the plurality of first extendingportions may be provided on the support surface of the protrudingportion. With such a configuration, the base substrate can be supportedwith respect to the housing by the first extending portions and thesecond extending portions scattered at a plurality of positionsseparated from each other. Thus, for example, as compared with a case inwhich the first extending portion and the second extending portion areformed in a wall shape along an edge portion of the base substrate, thebase substrate can be stably supported with respect to the housing whilea weight of the first extending portions and the second extendingportions is reduced.

The base substrate may have a plurality of protruding portions disposedapart from each other, and the first extending portion and the secondextending portion may be provided on each of the plurality of protrudingportions. With such a configuration, it is possible to easily realize aconfiguration which achieves the above-described effect by providing thefirst extending portion and the second extending portion for eachprotruding portion.

The radiation detection panel may be formed in a rectangular shape whenseen in the first direction, and the plurality of protruding portionsmay be provided at positions corresponding to four corners of theradiation detection panel. With such a configuration, since four cornersof the base substrate can be sandwiched by the first wall portion andthe second wall portion via the first extending portion and the secondextending portion in a well-balanced manner, the base substrate can besupported more stably with respect to the housing.

The housing may have a third wall portion which extends in the firstdirection and connects the first wall portion to the second wallportion, the third wall portion may be formed in a rectangular ringshape when seen in the first direction, a recess which avoidsinterference with the protruding portion, the first extending portion,and the second extending portion may be formed in each corner portion ofthe third wall portion, and a thickness of the third wall portion in therecess may be smaller than a thickness of the third wall portion on aside portion of the third wall portion which connects the adjacentcorner portions of the third wall portion. When a thickness of the thirdwall portion is constant (that is, a thickness at the corner portion isthe same as a thickness at the side portion), it is necessary toincrease an exterior size of the housing when seen in the firstdirection by an amount that it is necessary to avoid interference withthe protruding portion at the corner portion. In this case, a proportionof a dead region in the radiation imaging device when seen in the firstdirection (that is, a ratio of a region other than a detection region toa region of the entire radiation imaging device) becomes large. On theother hand, with such a configuration, it is possible to reduce theproportion of the dead region by forming the recess.

The first wall portion may have a shield member which is disposed to bein surface contact with the third wall portion and shieldselectromagnetic waves, and the first wall portion may be screwed to theside portion of the third wall portion and the first extending portion.With such a configuration, excellent surface contact between the firstwall portion and the third wall portion can be achieved on the entiresurface of the third wall portion which faces the first wall portion byscrewing the first wall portion to the side portion of the third wallportion and the first extending portion (that is, a portion close to thecorner portion of the third wall portion). Thus, an electromagneticshield effect can be effectively enhanced.

Advantageous Effects of Invention

According to one aspect of the disclosure, it is possible to provide aradiation imaging device capable of stably supporting a base substrateon which a radiation detection panel is supported.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of a radiation imaging device of one embodiment.

FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1 .

FIG. 3 is an enlarged plan view of a part of a radiation detectionpanel.

FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3 .

FIG. 5 is a diagram showing an internal configuration of a lightreceiving part and an IC chip.

FIG. 6 is a diagram for explaining a positional relationship between aconnection region and a base substrate.

FIG. 7 is a diagram showing a relationship between a distance from aheater and a temperature in the radiation detection panel.

FIG. 8 is a diagram showing an example of a manufacturing process of theradiation imaging device.

FIG. 9 is a diagram showing the example of the manufacturing process ofthe radiation imaging device.

FIG. 10 is a diagram showing the example of the manufacturing process ofthe radiation imaging device.

FIG. 11 is a diagram showing the example of the manufacturing process ofthe radiation imaging device.

FIG. 12 is a diagram showing an arrangement example of an electrode pad.

FIG. 13 is a diagram showing a modified example of the base substrate.

FIG. 14 is a diagram showing an arrangement example of a first extendingportion.

DESCRIPTION OF EMBODIMENTS

Hereinafter, embodiments of the disclosure will be described in detailwith reference to the accompanying drawings. In the description of thedrawings, the same reference numerals are used for the same orequivalent elements, and duplicate description thereof will be omitted.The disclosure is not limited to these examples, but is shown by thescope of claims and is intended to include all modifications within themeaning and scope equivalent to the scope of claims. For ease ofunderstanding, XYZ orthogonal coordinate systems are shown in FIGS. 1 to4, 6 and 8 to 11 .

FIG. 1 is a plan view of a radiation imaging device 1 according to anembodiment of the disclosure. FIG. 2 is a cross-sectional view takenalong line II-II of FIG. 1 . However, in FIG. 1 , a top wall 11 and ascrew member 14 are not shown. The radiation imaging device 1 is, forexample, a large-area flat panel sensor used in a medical X-ray imagingsystem. As shown in FIGS. 1 and 2 , the radiation imaging device 1includes a housing 10, a base substrate 20, a radiation detection panel30, a flexible circuit substrate 40, a control substrate 50, and aradiation shielding member 60.

The housing 10 is a hollow container having a substantially rectangularparallelepiped shape. The housing 10 has a top wall 11 (a first wallportion), a bottom wall 12 (a second wall portion), and a side wall 13(a third wall portion). The top wall 11 and the bottom wall 12 are eachformed in a rectangular plate shape which extends along an XY plane, andface each other. The side wall 13 extends along an XZ plane or an YZplane, and connects an edge portion of the top wall 11 with an edgeportion of the bottom wall 12. That is, the side wall 13 is formed in arectangular ring shape when seen in a Z direction. The housing 10accommodates the base substrate 20, the radiation detection panel 30,the flexible circuit substrate 40, the control substrate 50, and theradiation shielding member 60.

The top wall 11 is configured of a member which allows radiation (forexample, X-rays) to be detected by the radiation imaging device 1 to betransmitted to the inside of the housing 10. The top wall 11 guides theradiation incident in the Z direction to the inside of the housing 10.That is, the Z direction is an incident direction of the radiation to bedetected. In the embodiment, the top wall 11 has a two-layer structure.Specifically, the top wall 11 includes a carbon fiber plate 111 providedon the side (the outer side) on which the radiation is incident, and ashield member 112 provided on an inner surface of the carbon fiber plate111 to shield electromagnetic waves. The shield member 112 is, forexample, an aluminum shield formed by adhering an aluminum foil to theinner surface of the carbon fiber plate 111.

The bottom wall 12 and the side wall 13 are formed of a metal material(for example, iron or the like) which blocks radiation. An upper surface13 a of the side wall 13 is in surface contact with the shield member112 and is electrically connected to the shield member 112. Thus,electromagnetic waves directed from the outside of the housing 10 to theinside of the housing 10 are shielded. Further, a plurality of screwholes 13 b are provided in the upper surface 13 a of the side wall 13.The screw member 14 is inserted through a through hole 11 a provided inthe top wall 11 and screwed into the screw hole 13 b. Accordingly, thetop wall 11 is fixed to the side wall 13.

The base substrate 20 is a member which supports the radiation detectionpanel 30, the control substrate 50, and the radiation shielding member60. The base substrate 20 is made of, for example, a metal such as iron,aluminum, stainless steel, a tungsten alloy, copper tungsten or thelike. As an example, in the embodiment, the base substrate 20 is made ofrelatively lightweight aluminum. The base substrate 20 has a supportsurface 20 a and a back surface 20 b on the side opposite to the supportsurface 20 a. The support surface 20 a is a surface which faces the topwall 11, and the back surface 20 b is a surface which faces the bottomwall 12. The support surface 20 a supports a substrate 31 of theradiation detection panel 30. The control substrate 50 is fixed to theback surface 20 b via, for example, one or more support members 55formed in a columnar shape which extends in the Z direction.

The radiation detection panel 30 has the substrate 31 formed in arectangular plate shape. The substrate 31 has a first surface 31 a onwhich a light receiving part 32 (a light receiving surface) is formed,and a second surface 31 b on the side opposite to the first surface 31a. The first surface 31 a is a surface which faces the top wall 11, andthe second surface 31 b is a surface which faces the bottom wall 12. Ascintillator 34 (a conversion part) is disposed on the light receivingpart 32. The scintillator 34 is formed by, for example, depositing ascintillator material containing CsI as a main component on the lightreceiving part 32. The scintillator 34 converts radiation incidentthrough the top wall 11 into light. Specifically, the scintillator 34outputs scintillation light having an intensity corresponding to anincident intensity of radiation to the light receiving part 32. Thus, aregion on the first surface 31 a in which the light receiving part 32 isformed serves as a detection region R for detecting radiation. Thedetection region R has, for example, a light receiving area (forexample, 40 cm×30 cm) having a side of about 30 cm to 40 cm.

The substrate 31 is, for example, a transparent glass substrate. Thesubstrate 31 is fixed to the base substrate 20 by the second surface 31b of the substrate 31 being fixed to the support surface 20 a of thebase substrate 20. For example, the second surface 31 b of the substrate31 is fixed to the support surface 20 a of the base substrate 20 via anadhesive member G (refer to FIG. 6 ) such as double-sided tape. Whenseen in the Z direction, at least the region in which the lightreceiving part 32 and the scintillator 34 are disposed is included inthe support surface 20 a. Further, the adhesive member G (refer to FIG.6 ) is provided at least in a region overlapping the light receivingpart 32 when seen in the Z direction. Further, an outer end portion ofthe adhesive member G is located further inward than an end portion (anend portion 21 a described later) of the base substrate 20 when seen inthe Z direction. On the first surface 31 a of the substrate 31, aplurality of electrode pads 33 are formed on the outside of thedetection region R. The plurality of electrode pads 33 are electricallyconnected to pixels P_(m,n) (refer to FIG. 3 ) formed in the lightreceiving part 32 via a wire (a reading wire and a row selection wire)described later. In the embodiment, as an example, 22 (11×2 sides)electrode pads 33 are formed on a peripheral edge portion of thesubstrate 31 in an X direction. Further, 14 (7×2 sides) electrode pads33 are formed on the peripheral edge portion of the substrate 31 in a Ydirection.

The flexible circuit substrate 40 is a circuit member electricallyconnected to the electrode pads 33. The flexible circuit substrate 40includes a flexible substrate 41 which can be deformed by bending or thelike, and an IC chip 42 mounted on the flexible substrate 41. Theflexible substrate 41 has, for example, a structure in which a circuitpattern made of a conductor foil (for example, copper or the like) isformed on a thin film insulator (for example, polyimide or the like).One end portion 41 a of the flexible substrate 41 is connected to theelectrode pads 33 via a connecting member 70. The connecting member 70is a member which generates an adhesive force by thermocompressionbonding, and is an anisotropic conductive material such as ananisotropic conductive film (ACF) or anisotropic conductive paste (ACP).The other end portion 41 b of the flexible substrate 41 is connected tothe control substrate 50 (a connector 51).

The control substrate 50 includes a circuit which controls an operationof the IC chip 42 (for example, an operation of vertical shift registers42 a and 42 b and signal connection parts 42 c and 42 d which will bedescribed later) and supplies electric power to the IC chip 42.Specifically, for example, electric power is supplied to the controlsubstrate 50 from an external power source (not shown) disposed on theoutside of the housing 10 (for example, the outside of the bottom wall12), and the electric power is supplied to the IC chip 42 via thecontrol substrate 50. The external power source may be disposed insidethe housing 10 (for example, a space between the control substrate 50and the bottom wall 12). However, from the viewpoint of curbinggeneration of measurement noise caused by the external power source, itis preferable that the external power source is disposed outside thehousing 10. The control substrate 50 is fixed to the back surface 20 bof the base substrate 20 via one or more of the above-described supportmembers 55. Further, the control substrate 50 is also fixed to thebottom wall 12 via a support member 56 similar to the support member 55.The support member 55 and the support member 56 may be integrally formedas a columnar member which supports the control substrate 50 whilepassing through the control substrate 50 in the Z direction. Such acolumnar member serves as a member which supports the base substrate 20with respect to the bottom wall 12 and supports the control substrate 50with respect to the bottom wall 12 and the base substrate 20.

Here, the IC chip 42 mounted on the flexible circuit substrate 40 and anAD converter 52 mounted on the control substrate 50 are parts (heatgenerating members) which are particularly likely to generate heat.Further, when heat from the IC chip 42 or the AD converter 52 istransferred to the radiation detection panel 30, noise may be generatedin an image acquired by the light receiving part 32. Therefore, in theembodiment, a heat sink member 57 is disposed between each of the ICchip 42 and the AD converter 52 and the bottom wall 12 to efficientlyrelease the heat generated from the IC chip 42 and the AD converter 52to the bottom wall 12 of the housing 10. The heat sink member 57 is, forexample, a gel sheet or the like of which a main material is silicone orthe like. As shown in FIG. 2 , when a distance between the IC chip 42 orthe AD converter 52 and the bottom wall 12 is large, a projection 12 awhich protrudes toward the top wall 11 side may be provided on a portionof the inner surface of the bottom wall 12 which overlaps the IC chip 42or the AD converter 52 when seen in the Z direction. According to such aprojection 12 a, the heat generated from the IC chip 42 or the ADconverter 52 can be appropriately released to the bottom wall 12 via theheat sink member 57 and the projection 12 a. Further, it is possible toutilize a portion in which the projection 12 a is not provided as aspace for accommodating various parts and the like by partially raisingthe inner surface of the bottom wall 12.

The control substrate 50 overlaps the scintillator 34 and the basesubstrate 20 when seen in the Z direction. That is, most of theradiation incident from the top wall 11 and directed to the controlsubstrate 50 is shielded by the scintillator 34 and the base substrate20. On the other hand, as in the embodiment, the IC chip 42 mounted onthe flexible circuit substrate 40 may be disposed at a position at whichit does not overlap the scintillator 34 and the base substrate 20 whenseen in the Z direction. That is, the radiation incident from the topwall 11 and directed to the IC chip 42 may not be shielded by thescintillator 34 and the base substrate 20. In this case, when nomeasures are taken, the IC chip 42 may be damaged by the radiation, anda malfunction of the IC chip 42 or the like may be caused. Therefore, inthe embodiment, the radiation shielding member 60 is provided to shieldthe radiation incident from the top wall 11 and directed to the IC chip42.

The radiation shielding member 60 is made of a material having highX-ray shielding ability such as lead and tungsten. In the embodiment, asan example, the radiation shielding member 60 is formed in a strip shapeand is provided at an edge portion of the back surface 20 b of the basesubstrate 20. A part of the radiation shielding member 60 protrudes tothe outside of the base substrate 20 to overlap the IC chip 42 when seenin the Z direction. The radiation shielding member 60 may be providedfor each of the IC chips 42, or one radiation shielding member 60 (thatis, a member formed in a size which overlaps the plurality of IC chipswhen seen in the Z direction) may be provided for a plurality of ICchips 42 adjacent to each other. In the embodiment, a weight of theradiation imaging device 1 is reduced by the base substrate 20 beingmade of relatively lightweight aluminum and the radiation shieldingmember 60 made of a relatively heavy material as described above beingprovided in part of a place in which radiation needs to be shielded.

The base substrate 20 includes a main body 21 which is formed in arectangular shape when seen in the Z direction (a first direction)orthogonal to the support surface 20 a, and a protruding portion 22which is formed at each of corner portions (four corners) of the mainbody 21 and protrudes to the outside of the main body 21. In theembodiment, as an example, the protruding portion 22 is formed in asubstantially rectangular shape of which corners are chamfered when seenin the Z direction. Further, the main body 21 and the protruding portion22 are integrally formed, and a thickness (a plate thickness) of theprotruding portion 22 is the same as a thickness of the main body 21.That is, the base substrate 20 is configured as a single plate having asubstantially uniform thickness.

When seen in the Z direction, an end portion of the base substrate 20corresponding to a portion in which the flexible circuit substrate 40 isconnected to the electrode pad 33 is located further inward (on thedetection region R side) than an end portion of the radiation detectionpanel 30 (that is, an end portion 31 c of the substrate 31).Specifically, the main body 21 is formed in a rectangular shape smallerthan the substrate 31 when seen in the Z direction, and the end portion21 a of the main body 21 is located further inward than the end portion31 c of the substrate 31. That is, the end portion of the base substrate20 (that is, the end portion 21 a of the main body 21) corresponding toeach of side portions (portions in which the electrode pad 33 is formed)of the radiation detection panel 30 is located further inward than theend portion 31 c of the substrate 31. Furthermore, in the embodiment,the base substrate 20 is formed not to overlap a connection region A inwhich the electrode pad 33, the connecting member 70, and the flexiblecircuit substrate 40 (the one end portion 41 a of the flexible substrate41) overlap each other when seen in the Z direction. That is, the endportion 21 a of the main body 21 is located further inward than an innerend portion A1 of the connection region A. Thus, a configuration inwhich the base substrate 20 does not overlap the connection region A (36connection regions A in the embodiment) when seen in the Z direction isrealized.

The protruding portion 22 protrudes further outward than the radiationdetection panel 30 at a position (as an example in the embodiment, thecorner portion of the main body 21) at which it does not overlap theflexible circuit substrate 40 when seen in the Z direction. That is,when seen in the Z direction, the protruding portion 22 protrudesfurther outward than the substrate 31. In the embodiment, the protrudingportion 22 protrudes further outward than an end portion (a bent portionwhich is a portion farthest from the end portion 31 c of the substrate31 in a direction parallel to the XY plane) of the flexible substrate 41when seen in the Z direction.

A first extending portion 81 which extends in the Z direction isprovided in the support surface 20 a of the protruding portion 22. As anexample in the embodiment, the first extending portion 81 is made ofaluminum. However, the first extending portion 81 may be formed of othermaterials. For example, the material of the first extending portion 81may be a metal other than aluminum such as iron, engineering plasticssuch as polyacetal (POM) and polyetheretherketone (PEEK), and the like.The first extending portion 81 is fixed to the protruding portion 22via, for example, a fixing member (for example, a screw or the like)which is not shown. In the embodiment, the first extending portion 81 isa columnar member which extends in the Z direction and serves as apositioning member for positioning the radiation detection panel 30(that is, the substrate 31). Specifically, the first extending portion81 has a guide groove 81 a which extends in the Z direction toaccommodate a corner portion 31 d of the substrate 31. The guide groove81 a is formed in an L shape to match a shape of the corner portion 31 dof the substrate 31 when seen in the Z direction. That is, the firstextending portion 81 has a shape in which a part (a square columnarportion corresponding to a space formed by the guide groove 81 a) of asquare columnar member (a member having the same shape as a secondextending portion 82 which will be described later) is cut out. In theembodiment, such a first extending portion 81 is provided correspondingto each of the four corners of the substrate 31. That is, the substrate31 can be positioned by disposing each of the corner portions 31 d ofthe substrate 31 inside the guide groove 81 a of each of the firstextending portions 81.

The first extending portion 81 is supported by the top wall 11. In theembodiment, a screw hole 81 b is formed in the surface of the firstextending portion 81 on the top wall 11 side. Then, the screw member 14is inserted through the through hole 11 a provided in the top wall 11and screwed into the screw hole 81 b. In this way, the first extendingportion 81 is supported by the top wall 11 and is also supported by theprotruding portion 22. That is, the base substrate 20 is supported bythe top wall 11 via the first extending portion 81. In the embodiment,the base substrate 20 (the protruding portion 22) is firmly fixed to thetop wall 11 via the first extending portion 81 by screwing.

The second extending portion 82 which is disposed at a position at whichit faces the first extending portion 81 with the protruding portion 22interposed therebetween and extends in the Z direction is provided inthe back surface 20 b of the protruding portion 22. As an example in theembodiment, the second extending portion 82 is made of aluminum.However, the same material as the above-described material of the firstextending portion 81 can be used as the material of the second extendingportion 82. The second extending portion 82 is supported by theprotruding portion 22 via, for example, a fixing member (for example, ascrew or the like) which is not shown. The first extending portion 81and the second extending portion 82 may be fixed to the protrudingportion 22 by being screwed from the first extending portion 81 side orthe second extending portion 82 side using a common screw, or may befixed to the protruding portion 22 by being individually screwed usingdifferent screws. Further, the second extending portion 82 is supportedby the bottom wall 12 by the same fixing means as that of the firstextending portion 81. For example, a screw hole (not shown) is formed ina surface of the second extending portion 82 on the bottom wall 12 side,and a screw member (not shown) is inserted through a through hole (notshown) provided in the bottom wall 12 and screwed into the screw hole.In this way, the second extending portion 82 is supported by theprotruding portion 22 and the bottom wall 12. That is, the basesubstrate 20 is supported by the bottom wall 12 via the second extendingportion 82. In the embodiment, the base substrate 20 (the protrudingportion 22) is firmly fixed to the bottom wall 12 via the secondextending portion 82 by screwing.

It is not necessary to form a groove portion corresponding to the guidegroove 81 a of the first extending portion 81 in the second extendingportion 82. Therefore, in the embodiment, the second extending portion82 is formed in a square columnar shape. That is, the second extendingportion 82 has a portion which overlaps the first extending portion 81when seen in the Z direction, and also has a portion which overlaps aspace having a square columnar shape formed by the guide groove 81 awhen seen in the Z direction. However, for example, in order tocommonize the members, the second extending portion 82 may be formedinto an L-shaped columnar member having the same dimension as that ofthe first extending portion 81 and may be disposed to completely overlapthe first extending portion 81 when seen in the Z direction.

As described above, in the embodiment, the first extending portion 81and the second extending portion 82 are provided on the protrudingportions 22 provided at the corner portions (the four corners) of themain body 21. That is, the first extending portion 81 and the secondextending portion 82 are provided at positions corresponding to thecorner portions 31 d of the radiation detection panel 30 (the substrate31). Additionally, the side wall 13 is formed in a rectangular ringshape when seen in the Z direction, and a recess 13 c is formed at acorner portion of the side wall 13 to avoid interference with theprotruding portion 22, the first extending portion 81, and the secondextending portion 82. A thickness t1 of the side wall 13 in the recess13 c is smaller than a thickness t2 of the side wall 13 in a sideportion which connects the adjacent corner portions. In the embodiment,the recess 13 c is formed at the corner portion of the side wall 13 tobe spaced apart from an outer edge of the protruding portion 22 whenseen in the Z direction by cutting out a part of an inner side surfaceof the side wall 13. Stress concentration on the corner portion of theside wall 13 is curbed by forming the recess 13 c having such a smallthickness at the corner portion of the side wall 13.

Here, the above-described screw hole 13 b is not provided in the recess13 c having a small thickness (a portion having the thickness t1), butis provided only in a side portion having a large thickness (a portionhaving the thickness t2). Therefore, the top wall 11 and the side wall13 are not fixed (not screwed) to each other at the corner portions (thefour corners) of the housing 10 when seen in the Z direction. However,instead, in the embodiment, as described above, the top wall 11 and thefirst extending portion 81 may be fixed to each other by the screwmember 14. That is, the top wall 11 and the side wall 13 are firmlyfixed to each other even at the corner portions of the housing 10. Thus,excellent surface contact between the shield member 112 of the top wall11 and the side wall 13 can be achieved even at the corner portions ofthe housing 10 (the portions to which the top wall 11 and the side wall13 are not directly screwed). As a result, leakage of electromagneticwaves from outside the housing 10 (invasion thereof into the housing 10)can be effectively curbed.

Further, an exterior of the housing 10 seen in the Z direction can bemade as small as possible by forming such a recess 13 c. That is, inorder to screw the top wall 11 and the side wall 13 at the cornerportions of the housing 10, it is also necessary to increase theexterior size of the housing 10 when seen in the Z direction to secure athickness of the side wall 13 required for providing the screw holes 13b at the corner portions of the housing 10. In this case, a proportionof a dead region in the radiation imaging device 1 when seen in the Zdirection (that is, a ratio of a region other than an effective lightreceiving area (the detection region R) to the entire region of theradiation imaging device 1) becomes large. On the other hand, it ispossible to reduce the proportion of the dead region while excellentsurface contact between the top wall 11 and the side wall 13 is ensuredby forming the recess 13 c and fixing the first extending portion 81 andthe top wall 11 to each other instead of fixing the top wall 11 and theside wall 13 at the corner portions of the housing 10 as described inthe embodiment.

Next, an operation (radiation detection) of the radiation imaging device1 will be described. In the embodiment, a vertical shift register (avertical scanning circuit) is formed on the IC chip 42 of the flexiblecircuit substrate 40 connected to the electrode pad 33 formed on theperipheral edge of the substrate 31 in the X direction. Specifically,the vertical shift register 42 a is formed by the IC chip 42 of theflexible circuit substrate 40 provided on a left peripheral edge portion(a left side) of the substrate 31 in FIG. 1 , and the vertical shiftregister 42 b is formed by the IC chip 42 of the flexible circuitsubstrate 40 provided on a right peripheral edge portion (a right side)of the substrate 31. Further, an amplifier chip (a signal connectionpart) for reading a signal is formed on the IC chip 42 of the flexiblecircuit substrate 40 connected to the electrode pad 33 formed on theperipheral edge of the substrate 31 in the Y direction. Specifically,the signal connection part 42 c is formed by the IC chip 42 of theflexible circuit substrate 40 provided on an upper peripheral edgeportion (an upper side) of the substrate 31 in FIG. 1 , and the signalconnection part 42 d is formed by the IC chip 42 of the flexible circuitsubstrate 40 provided on a lower peripheral edge portion (lower side) ofthe substrate 31. As described above, in the embodiment, a configurationin which a signal reading line (a data line) is divided into upper andlower parts is adopted to reduce noise in signal reading and to improvea speed thereof.

A detailed configuration of the light receiving part 32 and the IC chip42 (the operation of the radiation imaging device 1) will be describedwith reference to FIGS. 3 to 5 . FIG. 3 is an enlarged plan view of apart of the radiation detection panel 30. FIG. 4 is a cross-sectionalview taken along line IV-IV of FIG. 3 . FIG. 5 is a diagram showing aninternal configuration of the light receiving part 32 and the IC chip42.

The light receiving part 32 is configured by arranging M×N pixels in Mrows and N columns in two dimensions. A pixel P_(m,n) shown in FIG. 3 isa pixel located in the mth row and the nth column. Here, in is aninteger of 1 or more and M or less, and n is an integer of 1 or more andN or less. In FIG. 3 , a column direction coincides with an X-axisdirection, and a row direction coincides with a Y-axis direction. Eachof a plurality of pixels P_(1,1) to P_(M,N) included in the lightreceiving part 32 includes a photodiode PD and a reading switch SW1. Abias voltage is applied to an anode terminal of the photodiode PD, andone end (one current terminal) of the reading switch SW1 is connected toa cathode terminal of the photodiode PD. Further, the other end (theother current terminal) of the reading switch SW1 is connected to acorresponding reading wire (for example, in the case of the pixelP_(m,n), an nth column reading wire L_(o,n)). A control terminal of thereading switch SW1 is connected to a corresponding row selection wire(for example, in the case of the pixel P_(m,n), an mth row selectionwire L_(v,m)).

As shown in FIG. 4 , a silicon film 35 is provided on the entire surfaceof the first surface 31 a of the substrate 31. Additionally, thephotodiode PD, the reading switch SW1, and the nth column reading wireL_(o,n) are formed on a surface of the silicon film 35. The photodiodePD, the reading switch SW1, and the nth column reading wire L_(o,n) arecovered with an insulating layer 36. A scintillator 34 is provided onthe insulating layer 36 to cover the entire detection region R of thefirst surface 31 a of the substrate 31. The photodiode PD is configuredto contain, for example, amorphous silicon.

The photodiode PD of the embodiment includes an n-type semiconductorlayer 91 made of n-type polycrystalline silicon, an i-type semiconductorlayer 92 made of i-type amorphous silicon provided on the n-typesemiconductor layer 91, and a p-type semiconductor layer 93 made ofp-type amorphous silicon provided on the i-type semiconductor layer 92.Further, the reading switch SW1 is a thin film transistor (TFT) made ofpolycrystalline silicon, and has a configuration as a field effecttransistor (FET). That is, the reading switch SW1 includes a channelregion 94, a source region 95 disposed along one side surface of thechannel region 94, a drain region 96 disposed along the other sidesurface of the channel region 94, and a gate insulating film 97 and agate electrode 98 formed on the channel region 94. The nth columnreading wire L_(o,n) is made of a metal. The scintillator 34 generatesscintillation light according to incident radiation, converts aradiation image into an optical image, and outputs the optical image tothe light receiving part 32.

In FIG. 5 , 4×4 pixels 100 are shown on behalf of M×N pixels P_(m,n)(m=1, . . . , M, n=1, . . . , N). Each of the pixels 100 includes thephotodiode PD and the reading switch SW1. The photodiode PD generates anelectric charge in an amount corresponding to an intensity of incidentlight, and accumulates the generated electric charge in a junctioncapacitance part. As described above, the reading switch SW1 isconnected to the row selection wire L_(V) corresponding to the row towhich the pixel 100 belongs. Here, the row selection wire LVcorresponding to the pixel P_(m,n) in the mth row is the above-describedmth row selection wire L_(v,m). The M row selection wires L_(v) areconnected to the vertical shift registers 42 a and 42 b. Each of thevertical shift registers 42 a and 42 b generates a row selection signalfor controlling a conduction state and a non-conduction state of thereading switch SW1 for each row and sequentially provides the rowselection signal to the row selection wire L_(V) in each of the rows.

The reading switch SW1 opens when the row selection signal output fromthe vertical shift register 42 a or 42 b to the row selection wire L_(v)is a non-significant value (for example, a low level). At this time, theelectric charge generated by the photodiode PD is accumulated in thejunction capacitance part without being output to a corresponding columnreading wire L_(o). Here, the column reading wire L_(o) corresponding tothe pixels P_(m,n) in the nth column is the above-described nth columnreading wire L_(o,n). On the other hand, when the row selection signalis a significant value (for example, a high level), the reading switchSW1 closes. At this time, the electric charge generated in thephotodiode PD and accumulated in the junction capacitance part is outputto the corresponding reading wire L_(o) via the reading switch SW1. Theoutput charge is sent to an integrating circuit 101 via the reading wireL_(o). In the embodiment, among the pixels 100 formed in the lightreceiving part 32, the reading switch SW1 of the pixel 100 located inthe row on the side of an upper side of the substrate 31 is connected tothe integrating circuit 101 of the signal connection part 42 c via thecorresponding reading wire L_(o). On the other hand, among the pixels100 formed in the light receiving part 32, the reading switch SW1 of thepixel 100 located in the row on the side of a lower side of thesubstrate 31 is connected to the integrating circuit 101 of the signalconnection part 42 d via the corresponding reading wire L_(o). A methodof dividing the row on the side of the upper side and the row on theside of the lower side of the substrate 31 is arbitrary. For example,when the number of rows on the side of the upper side of the substrate31 is N1, and the number of rows on the side of the lower side of thesubstrate 31 is N2, any of relationships “N1=N2”, “N1>N2”, and “N1<N2”may be established.

The integrating circuit 101 has a so-called charge integration typeconfiguration including an amplifier 101 a, a capacitance element 101 b,and a discharge switch 101 c. The capacitance element 101 b and thedischarge switch 101 c are connected in parallel with each other and areconnected between an input terminal and an output terminal of theamplifier 101 a. The input terminal of the amplifier 101 a is connectedto the column reading wire L_(o). A reset control signal RE is providedto the discharge switch 101 c via a reset wire L_(R).

The reset control signal RE instructs an opening and closing operationof the discharge switch 101 c of each of N integrating circuits 101. Forexample, when the reset control signal RE is a non-significant value(for example, a high level), the discharge switch 101 c is closed, theelectric charge in the capacitance element 101 b is discharged, and anoutput voltage value of the integrating circuit 101 is initialized.Further, when the reset control signal RE is a significant value (forexample, a low level), the discharge switch 101 c is opened, theelectric charge input to the integrating circuit 101 is accumulated inthe capacitance element 101 b, and a voltage value corresponding to theaccumulated electric charge is output from the integrating circuit 101.

Each of the signal connection parts 42 c and 42 d further includes Nholding circuits 102 and a horizontal shift register 103. Each of theholding circuits 102 includes an input switch 102 a, an output switch102 b, and a voltage holding part 102 c. One end of the voltage holdingpart 102 c is connected to an output end of the integrating circuit 101via the input switch 102 a, and the other end of the voltage holdingpart 102 c is connected to a voltage output wire L_(OUT) via the outputswitch 102 b. A holding control signal Hd is provided to the inputswitch 102 a via a holding wire L_(H). The holding control signal Hdinstructs an opening and closing operation of the input switches 102 aof each of the N holding circuits 102. A column selection signal isprovided to the output switch 102 b of the holding circuit 102 from thehorizontal shift register 103. The column selection signal instructs anopening and closing operation of the output switch 102 b of the holdingcircuit 102 in the corresponding column.

When the holding control signal Hd changes from a high level to a lowlevel, the input switch 102 a changes from a closed state to an openstate, and the voltage value input to the holding circuit 102 at thattime is held by the voltage holding part 102 c. After that, when thecolumn selection signal from the horizontal shift register 103sequentially changes from the low level to the high level for each ofthe columns, the output switch 102 b is sequentially closed, and thevoltage value held in the voltage holding part 102 c is sequentiallyoutput to the voltage output wire L_(OUT) for each of the columns.

Next, with reference to FIG. 6 , a positional relationship between theconnection region A and the end portion 21 a of the base substrate 20(the main body 21) will be described. As shown in FIG. 6 , the one endportion 41 a of the flexible circuit substrate 40 is connected to theelectrode pad 33 via the connecting member 70 by sandwiching theconnecting member 70 between heaters H1 and H2 from above and below andheating (thermocompression bonding) it in a state in which theconnecting member 70 is sandwiched between the one end portion 41 a andthe electrode pad 33. The heater H1 (a first heater) is a crimping jigdisposed on the side opposite to the connecting member 70 with theflexible circuit substrate 40 interposed therebetween. The heater H1 isa cemented carbide made of, for example, tungsten carbide and cobalt.The heater H2 (a second heater) is a crimping jig disposed on the sideopposite to the connecting member 70 with the heater H1 and theradiation detection panel 30 (that is, the substrate 31) interposedtherebetween. The heater H2 is, for example, quartz glass.

When the flexible circuit substrate 40 is connected to the electrode pad33, a surface H1 a (a surface which faces the one end portion 41 a) ofthe heater H1 is brought into contact with the one end portion 41 a ofthe flexible substrate 41 to overlap at least the connection region Awhen seen in the Z direction. Further, a surface H2 a (a surface of thesubstrate 31 which faces the second surface 31 b) of the heater H2 isbrought into contact with the second surface 31 b of the substrate 31 tooverlap at least the connection region A when seen in the Z direction.In this state, for example, heating is performed for several seconds bythe heater H1 heated to 190° C. and the heater H2 fixed at 40° C. Inorder to perform such thermocompression bonding (particularly, contactof the heater H2 with the second surface 31 b of the substrate 31), adistance d from the inner end portion A1 of the connection region A tothe end portion of the base substrate 20 (the end portion 21 a of themain body 21) is preferably 10 μm or more to curb interference betweenthe heater H2 and the base substrate 20 during a work.

On the other hand, any of the heat generated from the heaters H1 and H2during the thermocompression bonding can be transferred to the lightreceiving part 32, the scintillator 34, and the adhesive member G viathe substrate 31. The heat transferred in this way may adversely affectthese members. Here, as described above, the light receiving part 32,the scintillator 34, and the adhesive member G are all located furtherinward than the end portion 21 a of the base substrate 20 when seen inthe Z direction. That is, a distance (a distance along the XY plane)from the inner end portion A1 of the connection region A to each of thelight receiving part 32, the scintillator 34, and the adhesive member Gis guaranteed to be longer than the distance d. Therefore, it ispossible to secure a distance (a separation distance longer than thedistance d) from the connection region A to each of the members (thelight receiving part 32, the scintillator 34, and the adhesive member G)by adjusting the distance d. From the viewpoint of curbing the adverseeffect of the heat generated from the heaters H1 and H2 on each of themembers as described above, the distance d is preferably 1 mm or more.

Further, when a material having a deliquescent property is used as thescintillator 34, a moisture-proof film (a protective film) formed byparylene or the like may be provided to cover the entire scintillator34. It is known that a moisture-proof property of such a moisture-prooffilm decreases at about 50° C. In such a case, the distance d may be setso that a temperature of the scintillator 34 (the moisture-proof film)can be curbed to a temperature required for maintaining themoisture-proof property (here, 50° C. or less).

FIG. 7 shows a simulation result when the thermocompression bonding isperformed for 8 seconds with the heater H1 at 200° C. and the heater H2at 40° C. (A) of FIG. 7 shows a relationship between a distance from theheater H1 (a distance along the Y axis in FIG. 6 ) and a temperature ofthe substrate 31 at a portion corresponding to the distance when thesubstrate 31 is a glass substrate (here, non-alkali glass having athermal conductivity of 1.2 W/mK). (B) of FIG. 7 shows a relationshipbetween the distance from the heater H1 and the temperature of thesubstrate 31 at the portion corresponding to the distance when thesubstrate 31 is a flexible substrate (here, a film material having athermal conductivity of 0.3 W/mK). When the substrate 31 is a glasssubstrate, the simulations have been performed for each of cases inwhich the thickness t of the substrate 31 is 0.3 mm, 0.5 mm, 0.7 mm, and0.9 mm. On the other hand, when the substrate 31 is a flexiblesubstrate, the simulations have been performed for each of cases inwhich the thickness t of the substrate 31 is 0.1 mm and 0.2 mm.

As shown in (A) of FIG. 7 , in the case in which the substrate 31 is theabove-described glass substrate, it is confirmed that when the distancefrom the heater H1 is about 3.5 mm or more, it can be curbed to 50° C.or less in any one of the thicknesses (0.3 mm, 0.5 mm, 0.7 mm, 0.9 mm)Also, as shown in (B) of FIG. 7 , in the case in which the substrate 31is the above-described flexible substrate, it is confirmed that when thedistance from the heater H1 is about 1.5 mm or more, it can be curbed to50° C. or less in any one of the thicknesses (0.1 mm, 0.2 mm). Here, adistance (a length in the Y direction) from a reference position of thedistance from the heater H1 to the inner end portion A1 of theconnection region A is 0.27 mm. Further, as described above, an edgeportion of the scintillator 34 is located further inward than the endportion 21 a of the base substrate 20 when seen in the Z direction.Therefore, from the viewpoint of curbing the temperature of thescintillator 34 (the moisture-proof film) to 50° C. or less, when thesubstrate 31 is the above-described glass substrate, the distance d ispreferably 3.23 mm or more, and when the substrate 31 is theabove-described flexible substrate, the distance d is preferably 1.23 mmor more.

Next, an example of a method for manufacturing the radiation imagingdevice 1 will be described with reference to FIGS. 8 to 11 .

First, as shown in (A) of FIG. 8 , the radiation detection panel 30 onwhich the scintillator 34 is formed is prepared. For example, thequality of the radiation detection panel 30 is determined by performingan image inspection such as probing on the radiation detection panel 30.Subsequently, the scintillator 34 is formed by depositing a scintillatormaterial such as CsI on a pixel area (the light receiving part 32) ofthe radiation detection panel 30 determined as a non-defective product.Thus, the radiation detection panel 30 shown in (A) of FIG. 8 isprepared.

Further, as shown in (B) of FIG. 8 , the base substrate 20 on which thefirst extending portion 81 and the second extending portion 82 aremounted is prepared. For example, the base substrate 20 including theabove-described main body 21 and protruding portion 22 is produced byperforming planar shape processing on a single metal plate.Subsequently, the first extending portion 81 is mounted on the supportsurface 20 a of the protruding portion 22 (each of the four protrudingportions 22 provided at the four corners of the main body 21 in theembodiment) by screwing or the like. Further, the second extendingportion 82 is mounted on the back surface 20 b of the protruding portion22 by screwing or the like. Further, the support member 55 for fixingthe control substrate 50 is mounted on the back surface 20 b of the mainbody 21. When the first extending portion 81 and the second extendingportion 82 are individually screwed using different screws, the secondextending portion 82 may not be necessarily mounted on the protrudingportion 22 at this stage. In this case, the second extending portion 82may be mounted on the protruding portion 22 at an arbitrary time pointprior to a step of accommodating the second extending portion 82 in abox portion of the housing which will be described later (refer to FIG.11 ). Further, the support member 55 may not be necessarily mounted onthe main body 21 at this stage and may also be mounted on the main body21 at an arbitrary time point prior to a mounting step of the controlsubstrate 50 (refer to (A) of FIG. 9 ) which will be described later.

Subsequently, as shown in (C) of FIG. 8 , the radiation detection panel30 (refer to (A) of FIG. 8 ) on which the scintillator 34 is formed isfixed to the support surface 20 a of the base substrate 20 (refer to (B)of FIG. 8 ) on which the first extending portion 81 and the secondextending portion 82 are mounted. Here, the radiation detection panel 30(the substrate 31) is positioned using the guide grooves 81 a of thefirst extending portion 81 provided at the four corners (the protrudingportions 22) of the base substrate 20 when seen in the Z direction.Subsequently, for example, the substrate 31 is fixed to the supportsurface 20 a of the base substrate 20 by an adhesive member G (refer toFIG. 6 ) such as a double-sided tape provided in advance on the secondsurface 31 b of the substrate 31. Here, the base substrate 20 isdisposed with respect to the radiation detection panel 30 not to overlapthe connection region A (refer to FIGS. 2 and 6 ) in which the electrodepad 33, the connecting member 70, and the flexible circuit substrate 40will overlap each other. In the embodiment, as a result of positioningthe substrate 31 by the guide groove 81 a of the first extending portion81, the end portion 21 a of the main body 21 of the base substrate 20 isdisposed further inward than the end portion 31 c of the substrate 31.Thus, the base substrate 20 is disposed not to overlap the connectionregion A. In a state shown in (C) of FIG. 8 , the radiation detectionpanel 30 and the base substrate 20 can be easily carried by gripping theportion (in the embodiment, at least one of the protruding portion 22,the first extending portion 81, and the second extending portion 82) atwhich the protruding portion 22 is provided. That is, handleability ofthe radiation detection panel 30 and the base substrate 20 is improvedby the portion in which the protruding portion 22 is provided.

Subsequently, as shown in (A) of FIG. 9 , the control substrate 50 isfixed to the back surface 20 b of the base substrate 20 via the supportmember 55.

Subsequently, as shown in (B) of FIG. 9 , the one end portion 41 a ofthe flexible circuit substrate 40 is connected to the electrode pad 33via the connecting member 70. For example, each of the IC chips 42 isinspected in advance, and the IC chip 42 determined as a non-defectiveproduct in the inspection is mounted on the flexible substrate 41.Subsequently, in the state in which the IC chip 42 is mounted on theflexible substrate 41, other inspections (for example, confirmation ofconduction between the IC chip 42 and the flexible substrate 41) arefurther performed. Through such inspections, the flexible circuitsubstrate 40 which will be mounted on the electrode pads 33 of thesubstrate 31 (36 electrode pads 33 in the embodiment) is prepared. Amounting order of the control substrate 50 and the flexible circuitsubstrate 40 may be reversed from the above. That is, the controlsubstrate 50 may be mounted on the base substrate 20 after the flexiblecircuit substrate 40 is mounted on the radiation detection panel 30.

Subsequently, the connecting member 70 is heated (thermocompressionbonded) by the heater H1 disposed on the side opposite to the connectingmember 70 with the flexible circuit substrate 40 (the one end portion 41a) interposed therebetween and the heater H2 disposed on the sideopposite to the connecting member 70 with the radiation detection panel30 (the substrate 31) interposed therebetween. As described above,interference between the heater H2 and the base substrate 20 isprevented by disposing the base substrate 20 not to overlap theconnection region A. Further, in the embodiment, since the substrate 31is a transparent glass substrate, a position of the electrode pad 33 canbe confirmed from the back surface (the second surface 31 b) side of thesubstrate 31. Thus, positioning of the heater H2 can be easilyperformed. Each of the electrode pads 33 and each of the flexiblecircuit substrates 40 are electrically connected by the above-describedprocessing. Although it is difficult to grip each of the side portionsof the substrate 31 after the flexible circuit substrate 40 is mountedon the electrode pads 33 disposed on each of the side portions of thesubstrate 31, the radiation detection panel 30 and the base substrate 20can be easily carried by gripping the portion at which the protrudingportion 22 is provided as described above.

Subsequently, as shown in (A) of FIG. 10 , a radiation shielding member60 for shielding radiation directed to the IC chip 42 mounted on each ofthe flexible circuit substrates 40 is provided at an edge portion of theback surface 20 b of the base substrate 20.

Subsequently, as shown in (B) of FIG. 10 , the other end portion 41 b ofeach of the flexible circuit substrates 40 is connected to the controlsubstrate 50 (the connector 51). Thus, each of the flexible circuitsubstrates 40 and the control substrates 50 are electrically connected.As a result, as shown in (B) of FIG. 10 , a detection unit 1 a before itis mounted in the housing 10 is completed.

Subsequently, an operation check is performed in the state shown in (B)of FIG. 10 . Here, when a defect in the flexible circuit substrate 40(for example, a malfunction of the IC chip 42 mounted on the flexiblecircuit substrate 40) is found, a repair work (a repair method of oneembodiment) is carried out according to the following procedure.

First, the other end portion 41 b of the flexible circuit substrate 40(hereinafter, “first flexible circuit substrate”) in which a defect isfound is removed from the connector 51, and the radiation shieldingmember 60 provided corresponding to the first flexible circuit substrateis removed from the back surface 20 b of the base substrate 20. Here,since the radiation shielding member 60 is partially provided for one oreach of the plurality of IC chips 42, it is only necessary to remove apart of the radiation shielding member 60, and workability is improved.Subsequently, the first flexible circuit substrate (the one end portion41 a) is removed from the electrode pad 33 in a state in which theradiation detection panel 30 is supported by the base substrate 20.Specifically, the connecting member 70 is removed from the electrode pad33 by heating the connecting member 70. The first flexible circuitsubstrate (the one end portion 41 a) can be removed from the electrodepad 33 by removing the connecting member 70 from the electrode pad 33 inthis way. As a result, a state shown in (A) of FIG. 9 is obtained. Theheating of the connecting member 70 when the first flexible circuitsubstrate is removed may be performed by the heaters H1 and H2 as in thecase of mounting, or may be performed by another method. For example,the connecting member 70 may be heated by blowing hot air onto one sideof the connecting member 70 (for example, the side of the first flexiblecircuit substrate (the one end portion 41 a)) using an air gun or thelike, instead of using the heaters H1 and H2.

Subsequently, the flexible circuit substrate 40 (a second flexiblecircuit substrate) which will be mounted on the radiation detectionpanel 30 is prepared. For example, when the above-described firstflexible circuit substrate can be repaired (for example, when the ICchip 42 mounted on the first flexible circuit substrate can be repairedby replacing it with another IC chip), a repair work of the firstflexible circuit substrate may be performed. In this case, the repairedfirst flexible circuit substrate is used as the second flexible circuitsubstrate. On the other hand, when the first flexible circuit substratecannot be repaired, a spare of the flexible circuit substrate preparedin advance may be used as the second flexible circuit substrate.

Subsequently, the second flexible circuit substrate is mounted on theelectrode pad 33 in a state in which the radiation detection panel 30 issupported by the base substrate 20. That is, as shown in (B) of FIG. 9 ,the second flexible circuit substrate is connected to the electrode pad33 via the connecting member 70 by heating (thermocompression bonding)the connecting member 70 with the heater H1 disposed on the sideopposite to the connecting member 70 with the second flexible circuitsubstrate (the one end portion 41 a) interposed therebetween and theheater H2 disposed on the side opposite to the connecting member 70 withthe radiation detection panel 30 (the substrate 31) interposedtherebetween. The repair of the flexible circuit substrate 40 (that is,the removal of the failed first flexible circuit substrate and thereinstallation of the second flexible circuit substrate (for example,the first flexible circuit substrate after repair or the spare part)) iscompleted by the above-described procedure. Then, a state shown in (B)of FIG. 10 is obtained by mounting again the radiation shielding member60 which was once removed for repairing the flexible circuit substrate40 on the edge portion of the back surface 20 b of the base substrate 20and mounting the other end portion 41 b of the second flexible circuitsubstrate on the connector 51. In this way, the flexible circuitsubstrate 40 can be repaired without removing the radiation detectionpanel 30 from the base substrate 20 by the base substrate 20 beingdisposed not to overlap the connection region A.

Subsequently, as shown in FIG. 11 , the detection unit 1 a shown in (B)of FIG. 10 is accommodated (fixed) in the box portion (the bottom wall12 and the side wall 13) of the housing. Specifically, the secondextending portion 82 is fixed to the bottom wall 12. Further, thecontrol substrate 50 is fixed to the bottom wall 12 via the supportmember 56. Further, the heat sink member 57 is disposed between the ICchip 42 or the AD converter 52 and the projection 12 a of the bottomwall 12. Subsequently, as shown in FIG. 2 , a lid portion (the top wall11) of the housing is screwed to the side wall 13 and the firstextending portion 81. In this way, the radiation imaging device 1 ismanufactured. The above-described repair work of the flexible circuitsubstrate 40 may be performed after the radiation imaging device 1 iscompleted. In this case, the above-described repair work may beperformed after the top wall 11 is removed from the side wall 13 and thefirst extending portion 81 and the detection unit 1 a is removed fromthe bottom wall 12 to bring the state shown in (B) of FIG. 10 .

Next, operational effects of the radiation imaging device 1 will bedescribed.

According to the radiation imaging device 1, the base substrate 20 (theprotruding portion 22) is sandwiched by parts of the housing 10 (the topwall 11 and the bottom wall 12) facing each other via the firstextending portion 81 and the second extending portion 82. Thus, the basesubstrate 20 can be stably supported with respect to the housing 10.Here, as a method of supporting the base substrate 20 with respect tothe housing 10, as shown in the above-described embodiment, there is,for example, a method of supporting the back surface 20 b of the basesubstrate 20 on the bottom wall 12 via the columnar support members 55and 56 (or a support member in which the support members 55 and 56 areintegrated to support the control substrate 50 while passing through thecontrol substrate 50 in the Z direction). In the embodiment, theabove-described support method is used in combination, but since thebase substrate 20 is supported by the housing 10 via the first extendingportion 81 and the second extending portion 82, it is possible to reducethe number of support members provided on the back surface 20 b of thebase substrate 20 as compared with a case in which the first extendingportion 81 and the second extending portion 82 are not provided. Thus,it is possible to make it difficult for an impact from the outside(particularly the bottom wall 12) to be transmitted to the back surface20 b of the base substrate 20. As a result, it is possible to reduce theimpact on the radiation detection panel 30 supported by the basesubstrate 20. Further, since the number of the support members 56 forsupporting the control substrate 50 with respect to the bottom wall 12can be reduced, it is possible to make it difficult for the impact fromthe outside (particularly the bottom wall 12) to be transmitted to thecontrol substrate 50. Further, since it is possible to reduce the numberof support members passing through the control substrate 50, it ispossible to improve a degree of freedom in designing a layout of thecontrol substrate 50 (a layout of circuits, wire, or the like mounted onthe control substrate 50).

Further, the first extending portion 81 serves as a positioning memberwhich positions the radiation detection panel 30 (the substrate 31).With such a configuration, since the first extending portion 81 makes itpossible to easily position the radiation detection panel 30 (thesubstrate 31) with respect to the support surface 20 a of the basesubstrate 20, assembling workability can be improved.

Further, the first extending portion 81 and the second extending portion82 may be integrally formed with the base substrate 20, but in theabove-described embodiment, the first extending portion 81 and thesecond extending portion 82 are formed separately from the basesubstrate 20. With such a configuration, warpage of the base substrate20 can be reduced as compared with a case in which the base substrate 20is integrally formed with at least one of the first extending portion 81and the second extending portion 82. Further, when the first extendingportion 81 or the second extending portion 82 is integrally formed withthe base substrate 20, it is necessary to cut out a relatively thickmetal plate, and thus a disadvantage in which material cost andman-hours are increased occurs. On the other hand, such a disadvantagecan be avoided by forming the first extending portion 81 and the secondextending portion 82 separately from the base substrate 20.

Further, as described above, the first extending portion 81 and thesecond extending portion 82 may be mounted on the protruding portion 22by a common mounting member (a screw or the like). With such aconfiguration, a relative positional relationship between the firstextending portion 81 and the second extending portion 82 can bemaintained with high accuracy, and the base substrate 20 can besupported more stably.

Further, the second extending portion 82 is larger than the firstextending portion 81 when seen in the Z direction, and the secondextending portion 82 has a portion which does not overlap the firstextending portion 81 when seen in the Z direction. In the embodiment,the second extending portion 82 is larger than the first extendingportion 81 by an amount that a groove portion corresponding to the guidegroove 81 a of the first extending portion 81 is not provided. Thebottom wall 12 of the housing 10 located on the side opposite to thefirst surface 31 a on which the detection region R of the radiationdetection panel 30 is formed (that is, facing the second surface 31 b)is usually a ground surface. Therefore, with such a configuration, thebase substrate 20 can be supported more stably by making the secondextending portion 82 supported by the bottom wall 12 larger than thefirst extending portion 81. Further, since the impact from the groundcontact surface side (the bottom wall 12) can be suitably absorbed bythe second extending portion 82, it is possible to make it difficult forthe impact to be transmitted to the radiation detection panel 30.

Further, a plurality of first extending portions 81 disposed apart fromeach other are provided, and a plurality of second extending portions 82disposed apart from each other to correspond to the plurality of firstextending portions 81 are provided on the support surface 20 a of theprotruding portion 22. In the embodiment, four first extending portions81 disposed apart from each other and four second extending portions 82corresponding to the four first extending portions 81 are provided. Withsuch a configuration, the base substrate 20 can be supported withrespect to the housing 10 by the first extending portions 81 and thesecond extending portions 82 scattered at a plurality of positions (inthe embodiment, the four corners of the base substrate 20) spaced apartfrom each other. Thus, for example, as compared with a case in which thefirst extending portion and the second extending portion are formed in awall shape along the edge portion of the base substrate 20, the basesubstrate 20 can be stably supported with respect to the housing 10while a weight of the first extending portion 81 and the secondextending portion 82 is reduced.

Further, the base substrate 20 has a plurality of (four in theembodiment) protruding portions 22 disposed apart from each other, andthe first extending portion 81 and the second extending portion 82 areprovided on each of the plurality of protruding portions 22. With such aconfiguration, a configuration in which the above-described effects areachieved can be easily realized by providing the first extending portion81 and the second extending portion 82 for each of the protrudingportions 22. Unlike the above-described embodiment, the plurality offirst extending portions 81 which are separated from each other and theplurality of second extending portions 82 which are separated from eachother may be provided on one protruding portion 22. Also in this case,the above-described effects can be obtained. However, it is possible toreduce an useless region (a region in which the first extending portion81 and the second extending portion 82 are not provided) in theprotruding portion 22 and it is possible to reduce a size and a weightof the protruding portion 22, by providing one first extending portion81 and one second extending portion 82 for each of the plurality ofprotruding portions 22 disposed in a dispersed manner as in theembodiment.

Further, the radiation detection panel 30 is formed in a rectangularshape when seen in the Z direction. The plurality of protruding portions22 are provided at positions corresponding to the four corners of theradiation detection panel 30. With such a configuration, since the fourcorners of the base substrate 20 can be sandwiched by the top wall 11and the bottom wall 12 via the first extending portion 81 and the secondextending portion 82 in a well-balanced manner, the base substrate 20can be supported more stably with respect to the housing 10.

Further, the side wall 13 is formed in a rectangular ring shape whenseen in the Z direction. The recess 13 c is formed at the corner portionof the side wall 13 to avoid interference with the protruding portion22, the first extending portion 81, and the second extending portion 82.The thickness t1 of the side wall 13 in the recess 13 c is smaller thanthe thickness t2 of the side wall 13 in the side portion which connectsthe corner portions of the adjacent side walls 13. When the thickness ofthe side wall 13 is made constant (that is, the thickness at the cornerportion is the same as the thickness at the side portion), it isnecessary to increase the exterior size of the housing 10 when seen inthe Z direction by an amount that it is necessary to avoid interferencewith the protruding portion 22 at the corner portion. In this case, theproportion of the dead region in the radiation imaging device 1 whenseen in the Z direction becomes large. On the other hand, with such aconfiguration, it is possible to reduce the proportion of the deadregion by forming the recess 13 c.

Further, the top wall 11 has a shield member 112 disposed to be insurface contact with the side wall 13, and the top wall 11 is screwed tothe side portion of the side wall 13 (the screw hole 13 b provided inthe side portion of the side wall 13) and the first extending portion 81(the screw hole 81 b provided in the first extending portion 81). Withsuch a configuration, excellent surface contact between the top wall 11and the side wall 13 can be achieved on the entire upper surface 13 a ofthe side wall 13 by screwing the top wall 11 to the side portion of theside wall 13 and the first extending portion 81 (that is, the portionclose to the corner portion of the side wall 13). Thus, anelectromagnetic shield effect can be effectively enhanced.

Further, the above-described method for manufacturing the radiationimaging device 1 includes a step of preparing the radiation detectionpanel 30 ((A) of FIG. 8 ), a step of supporting the second surface 31 bof the radiation detection panel 30 on the support surface 20 a of thebase substrate 20 ((C) of FIG. 8 ), and a step of connecting theflexible circuit substrate 40 to the electrode pad 33 via the connectingmember 70 ((B) of FIG. 9 ). Additionally, In the supporting step, thebase substrate 20 is disposed with respect to the radiation detectionpanel 30 so that the end portion 21 a of the base substrate 20 islocated further inward than the inner end portion A1 of the connectionregion A (refer to FIG. 6 ) in which the electrode pad 33, theconnecting member 70, and the flexible circuit substrate 40 will overlapeach other when seen in the Z direction. Also, in the connecting step,the connecting member 70 is heated by the heater H1 disposed on the sideopposite to the connecting member 70 with the flexible circuit substrate40 interposed therebetween and the heater H2 disposed on the sideopposite to the connecting member 70 with the radiation detection panel30 interposed therebetween. According to such a manufacturing method, inthe supporting step, the flexible circuit substrate 40, the connectingmember 70, and the radiation detection panel 30 can be sandwichedbetween the heater H1 and the heater H2 and can be thermocompressionbonded by disposing the base substrate 20 not to overlap the connectionregion A. That is, when the flexible circuit substrate 40 and theelectrode pad 33 are connected, it is possible to prevent theinterference between the heater H2 and the base substrate 20. Thus, theflexible circuit substrate 40 can be connected to the radiationdetection panel 30 in a state in which the radiation detection panel 30is stably supported by the base substrate 20. Further, a sufficientconnection strength can be ensured at a lower heating temperature (aheater temperature) by heating from both sides of the connecting member70 (the flexible circuit substrate 40 side and the radiation detectionpanel 30 side) with the heaters H1 and H2 as described above, ascompared with the case in which the heating is performed from one sideof the connecting member 70. Therefore, according to such amanufacturing method, it is also possible to secure the connectionstrength while the adverse effect of the heat during the heating on theradiation detection panel 30 and the like (for example, the scintillator34 and the like) is curbed.

However, the manufacturing procedure of the radiation imaging device 1is not limited to the above-described procedure, and for example, theflexible circuit substrate 40 may be connected to the electrode pad 33of the radiation detection panel 30 before the radiation detection panel30 is supported by the base substrate 20. That is, the flexible circuitsubstrate 40 may be connected to the radiation detection panel 30 in astate in which the radiation detection panel 30 is not supported by thebase substrate 20. In any case, since the shape and arrangement of thebase substrate 20 are designed not to overlap the connection region A, adegree of freedom of the work procedure at the time of manufacturing theradiation imaging device 1 is improved. Specifically, a timing forcarrying out the step of connecting the flexible circuit substrate 40 tothe radiation detection panel 30 can be arbitrarily selected. That is,the flexible circuit substrate 40 can be connected to the radiationdetection panel 30 before or after the radiation detection panel 30 issupported by the base substrate 20.

Moreover, the above-described repair method of the radiation imagingdevice 1 includes a step of removing the first flexible circuitsubstrate from the electrode pad 33 in a state in which the radiationdetection panel 30 is supported by the base substrate 20, and a step ofconnecting the second flexible circuit substrate to the electrode pad 33via the connecting member 70 by heating the connecting member 70 withthe heater H1 disposed on the side opposite to the connecting member 70with the second flexible circuit substrate (the first flexible circuitsubstrate after repair or another flexible circuit substrate) interposedtherebetween and the heater H2 disposed on the side opposite to theconnecting member 70 with the radiation detection panel 30 interposedtherebetween in the state in which the radiation detection panel 30 issupported by the base substrate 20. According to such a repair method,the repair (the removing step and the connecting step) of the flexiblecircuit substrate 40 can be performed without removing the radiationdetection panel 30 from the base substrate 20 by disposing the basesubstrate 20 not to overlap the connection region A. Therefore,according to the above-described repair method, the repair work of theflexible circuit substrate 40 can be easily performed.

(Appendix 1)

The radiation imaging device 1 includes the radiation detection panel 30having the first surface 31 a on which the detection region R fordetecting radiation is formed and the electrode pad 33 is formed outsidethe detection region R and the second surface 31 b on the side oppositeto the first surface 31 a, the base substrate 20 having the supportsurface 20 a which faces the second surface 31 b of the radiationdetection panel 30 and supports the radiation detection panel 30, andthe flexible circuit substrate 40 connected to the electrode pad 33 viaa connecting member 70. The end portion 21 a of the base substrate 20 islocated further inward than the inner end portion A1 of the connectionregion A in which the electrode pad 33, the connecting member 70, andthe flexible circuit substrate 40 overlap each other when seen in the Zdirection orthogonal to the support surface 20 a. In the radiationimaging device 1, when the flexible circuit substrate 40 is connected tothe electrode pad 33, it may be necessary to heat the flexible circuitsubstrate 40, the connecting member 70, and the radiation detectionpanel 30 with the heaters H1 and H2 from both sides in the Z direction.That is, for example, when a member which generates an adhesive force bythermocompression bonding, such as an anisotropic conductive material,is used as the connecting member 70, thermocompression bonding by theabove heaters H1 and H2 is required. On the other hand, in the radiationimaging device 1, the end portion 21 a of the base substrate 20 islocated further inward than the inner end portion A1 of the connectionregion A (all the connection regions A in the embodiment) when seen inthe Z direction. Therefore, it is possible to avoid interference betweenthe heater H2 disposed on the second surface 31 b side of the radiationdetection panel 30 and the base substrate 20. Thus, when the repair(repair, replacement, or the like) of the flexible circuit substrate 40is required, the repair of the flexible circuit substrate 40 can beperformed without removing the radiation detection panel 30 from thebase substrate 20. Therefore, according to the radiation imaging device1, the repair work of the flexible circuit substrate 40 can be easilyperformed.

Further, when the end portion 21 a of the base substrate 20 is locatedfurther outward than the end portion 31 c of the radiation detectionpanel 30 when seen in the Z direction, it is necessary to route theflexible circuit substrate 40 further outward than the end portion 21 aof the base substrate 20. The flexible circuit substrate 40 becomeslonger by an amount that such routing is required, and noise easily getson the signal transmitted through the flexible circuit substrate 40. Onthe other hand, in the radiation imaging device 1, the end portion 21 aof the base substrate 20 is located further inward than the inner endportion A1 of the connection region A when seen in the Z direction (thatis, it is located further inward than the end portion 31 c of theradiation detection panel 30). Therefore, it is not necessary to routethe flexible circuit substrate 40 as described above, and the overalllength of the flexible circuit substrate 40 can be shortened. As aresult, it is possible to curb noise in the signal transmitted via theflexible circuit substrate 40.

Further, the radiation detection panel 30 is formed in a rectangularshape when seen in the Z direction, and one or more connection regions Aare formed on at least one side portion of the radiation detection panel30. In the embodiment, as an example, a plurality of connection regionsA are formed on each of all (four) side portions. The end portion 21 aof the base substrate 20 is located further inward than the inner endportions A1 of all the connection regions A formed on at least one sideportion (each of the side portions in the embodiment) when seen in the Zdirection. With such a configuration, a position of the outer endportion 40 a of the flexible circuit substrate 40 connected to theconnection region A at the at least one side portion when seen in the Zdirection can be brought closer to the end portion 31 c of the radiationdetection panel 30 without interfering with the end portion 21 a of thebase substrate 20. That is, the outer end portion 40 a of the flexiblecircuit substrate 40 at the at least one side portion can be located asinward as possible. Thus, the size of the housing 10 when seen in the Zdirection can be reduced, and the radiation imaging device 1 can beminiaturized.

Further, the radiation imaging device 1 includes the scintillator 34which is disposed on the first surface 31 a and converts radiationconstituting the detection region R into light, the end portion 21 a ofthe base substrate 20 is located further outward than the detectionregion R when seen in the Z direction, and the distance d (refer to FIG.6 ) between the inner end portion A1 of the connection region A and theend portion 21 a of the base substrate 20 in a direction along the XYplane (in a second direction) may be 1 mm or more. With such aconfiguration, it is possible to secure a certain distance (at least 1mm or more) between the heater H1 which heats the connecting member 70and the scintillator 34 when the flexible circuit substrate 40 isconnected to the electrode pad 33. As a result, the adverse effect ofthe heat from the heater H1 on the scintillator 34 can be curbed.Further, as described above, a moisture-proof film having amoisture-proof property may be provided at the scintillator 34. Such amoisture-proof film has a property that it is particularly sensitive toheat. With such a configuration, it is possible to curb an adverseeffect of the heat from the heater H1 on the scintillator 34 (includingthe moisture-proof film) having such a particularly heat-sensitiveproperty.

Further, the base substrate 20 has the protruding portion 22 whichprotrudes further outward than the radiation detection panel 30 (thesubstrate 31) at a position at which it does not overlap the flexiblecircuit substrate 40 when seen in the Z direction. With such aconfiguration, since the protruding portion 22 can be used as a grippingportion in a state in which the radiation detection panel 30 issupported by the base substrate 20, it is possible to improvehandleability at the time of manufacturing or repairing the radiationimaging device 1.

(Appendix 2)

The radiation imaging device 1 includes the radiation detection panel 30having the first surface 31 a on which the detection region R fordetecting radiation is formed and the second surface 31 b on the sideopposite to the first surface 31 a, the base substrate 20 having thesupport surface 20 a which faces the second surface 31 b of theradiation detection panel 30 and supports the radiation detection panel30, and the flexible circuit substrate 40 connected to the radiationdetection panel 30. The end portion 21 a of the base substrate 20corresponding to the portion to which the flexible circuit substrate 40is connected is located further inward than the end portion 31 c of theradiation detection panel 30 when seen in the Z direction orthogonal tothe support surface 20 a, and the base substrate 20 has the protrudingportion 22 which protrudes further outward than the radiation detectionpanel 30 at a position at which it does not overlap the flexible circuitsubstrate 40 when seen in the Z direction. In the radiation imagingdevice 1, the end portion 21 a of the base substrate 20 corresponding tothe portion to which the flexible circuit substrate 40 is connected islocated further inward than the end portion 31 c of the radiationdetection panel 30 (the substrate 31). Thus, when it is necessary toconnect the other end portion 41 b of the flexible circuit substrate 40to the control substrate 50 disposed on the back surface 20 b of thebase substrate 20 as in the embodiment, interference between theflexible circuit substrate 40 and the base substrate 20 can beappropriately prevented.

Further, from the viewpoint of reducing the proportion of theabove-described dead region (that is, the ratio of the region other thanthe effective light receiving area (the detection region R) to theentire region of the radiation imaging device 1), preferably, aprotruding length of the flexible circuit substrate 40 from the endportion 31 c of the substrate 31 when seen in the Z direction is assmall as possible. Here, the protruding length is a separation distancebetween the outer end portion 40 a (a bent portion which is farthestfrom the end portion 31 c of the substrate 31 in a direction parallel tothe XY plane) of the flexible circuit substrate 40 and the end portion31 c of the substrate 31 when seen in the Z direction. Since the endportion 21 a of the base substrate 20 is located further inward than theend portion 31 c of the radiation detection panel 30 (the substrate 31),the protrusion length can be made as small as possible. Specifically,when the end portion 21 a of the base substrate 20 is located furtheroutward than the end portion 31 c, there is a restriction that theprotruding length should be larger than the distance between the endportion 31 c and the end portion 21 a of the base substrate 20. On theother hand, since the end portion 21 a of the base substrate 20 islocated further inward than the end portion 31 c of the radiationdetection panel 30 (the substrate 31), the above restriction does notoccur.

Further, the base substrate 20 has the protruding portion 22 whichprotrudes further outward than the radiation detection panel 30 (thesubstrate 31) at a position at which it does not overlap the flexiblecircuit substrate 40 when seen in the Z direction. Thus, since theprotruding portion 22 can be used as a gripping portion in the state inwhich the radiation detection panel 30 is supported by the basesubstrate 20, handleability of the base substrate 20 can be improved.

Further, the protruding portions 22 are formed at at least twolocations. In this case, the base substrate 20 can be stably gripped attwo locations. Further, the protruding portions 22 may be formed at atleast three locations or at least four locations. In the embodiment, theprotruding portions 22 are formed at four locations. In this case, thebase substrate 20 can be gripped more stably.

Further, the substrate 31 (the radiation detection panel 30) is formedin a rectangular shape when seen in the Z direction. The protrudingportion 22 is provided at a position corresponding to the corner portionof the radiation detection panel 30. The handleability of the basesubstrate 20 can be improved by providing the protruding portion 22 atthe position corresponding to the corner portion of the substrate 31while each of the side portions of the substrate 31 is used as a spaceconnected to the flexible circuit substrate 40 (that is, a region inwhich the electrode pad 33 is formed). In the embodiment, the protrudingportions 22 are formed at the four corners of the base substrate 20, andthe protruding portions 22 are fixed to the housing 10 via the firstextending portion 81 and the second extending portion 82. Thus, the basesubstrate 20 is supported in a well-balanced manner with respect to thehousing 10 via the protruding portions 22 formed at the four cornersthereof. Further, in this case, the base substrate 20 is supported onthe housing 10 by the protruding portion 22 formed at a position as faras possible from the radiation detection panel 30 when seen in the Zdirection. Accordingly, for example, even when the housing 10 isdeformed by an external force applied to the housing 10, it is possibleto preferably curb spreading of an influence of the deformation of thehousing 10 to the radiation detection panel 30 via the base substrate20.

Further, the radiation detection panel 30 is formed in a rectangularshape when seen in the Z direction, and one or more flexible circuitsubstrates 40 are connected to at least one side portion of theradiation detection panel 30. In the embodiment, as an example, aplurality of flexible circuit substrates 40 are connected to each of all(four) side portions. The end portion 21 a of the base substrate 20corresponding to the portion to which all the flexible circuitsubstrates 40 are connected at at least one side portion is locatedfurther inward than the end portion 31 c of the radiation detectionpanel 30. With such a configuration, positions of the outer end portions40 a of all the flexible circuit substrates 40 at at least one sideportion when seen in the Z direction can be brought closer to the endportion 31 c of the radiation detection panel 30 without interferingwith the end portion 21 a of the base substrate 20. That is, the outerend portion 40 a of the flexible circuit substrate 40 at at least oneside portion can be located as inward as possible. Thus, the size of thehousing 10 when seen in the Z direction can be reduced, and theradiation imaging device 1 can be miniaturized.

Although the preferred embodiments of the disclosure have been describedin detail, the disclosure is not limited to the above-describedembodiment. For example, not only the above-described materials andshapes but also various materials and shapes can be adopted as thematerial and shape of each of the parts.

In the above-described embodiment, the vertical shift registers 42 a and42 b and the signal connection parts 42 c and 42 d are all externallymounted via the flexible circuit substrate 40. Further, in considerationof reading performance (noise, reading speed, and the like), theelectrode pads 33 for connecting the vertical shift registers 42 a and42 b are disposed on both the left and right sides of the detectionregion R, and the electrode pads 33 for connecting the signal connectionparts 42 c and 42 d are disposed on both the upper and lower sides ofthe detection region R. That is, in the above-described embodiment, asshown in (A) of FIG. 12 , a plurality of electrode pads 33 are disposedon the four sides surrounding the detection region R. However, theelectrode pads 33 may not be necessarily disposed on all the four sides.Further, the number of electrode pads 33 disposed on each of the sidesand an arrangement interval thereof are not particularly limited.

For example, one of the vertical shift registers 42 a and 42 b or one ofthe signal connection parts 42 c and 42 d may be omitted. In this case,as shown in (B) of FIG. 12 , the electrode pads 33 are disposed alongthree sides of the substrate 31. Further, one of the vertical shiftregisters 42 a and 42 b and one of the signal connection parts 42 c and42 d may be omitted. In this case, as shown in (C) of FIG. 12 , theelectrode pads 33 are disposed along two sides of the substrate 31.Further, for example, the circuit corresponding to the vertical shiftregisters 42 a and 42 b may be disposed on the substrate 31 instead ofthe external IC chip 42. Further, one of the signal connection parts 42c and 42 d may be omitted. In this case, as shown in (D) of FIG. 12 ,the electrode pads 33 are disposed along one side of the substrate 31.For example, arrangement of such a circuit can be easily performed byconfiguring the substrate 31 as a TFT panel using low-temperaturepolysilicon.

Further, as shown in (E) of FIG. 12 , a plurality of (here, two as anexample) electrode pads 33 may be disposed at relatively wide intervalson the side portions of the substrate 31 (here, two sides on both theleft and right sides) at which the electrode pads 33 are provided. Inthe example, a relatively wide space in which the electrode pads 33 arenot disposed is formed at center portions of the two sides on both theleft and right sides. Further, as shown in (F) of FIG. 12 , only oneelectrode pad 33 may be disposed on the side portion of the substrate 31(here, two sides on both the left and right sides) on which theelectrode pad 33 is provided, and a relatively wide space may be formedon both sides of the electrode pad 33. Then, as shown in (B) to (F) ofFIG. 12 , when the side portion in which the electrode pad 33 is notformed or the relatively wide space in which the electrode pad 33 is notprovided is provided on the substrate 31, the protruding portion 22(refer to, for example, (E) to (I) of FIG. 13 ) may be disposed on theportion corresponding to the side portion or the space.

In the above-described embodiment, the protruding portions 22 areprovided at the four corners of the main body 21, but the arrangementand the number of the protruding portions 22 are not limited to theabove example. For example, the protruding portions 22 may be providedat one corner portion as shown in (A) of FIG. 13 , may be provided attwo adjacent corner portions as shown in (B) of FIG. 13 , may beprovided at two corner portions which are diagonal to each other asshown in (C) of FIG. 13 , or may be provided at three corner portions asshown in (D) of FIG. 13 .

Further, the position at which the protruding portion 22 is provided isnot limited to the corner portion of the main body 21, and may be theside portion of the main body 21. In this case, for example, theprotruding portion 22 may be provided on one side as shown in (E) ofFIG. 13 , may be provided on two sides adjacent to each other as shownin (F) of FIG. 13 , may be provided on two sides facing each other asshown in (G) of FIG. 13 , may be provided on three sides as shown in (H)of FIG. 13 , or may be provided on four sides as shown in (I) of FIG. 13. Further, in the examples of (F) to (I) of FIG. 13 , the protrudingportion 22 is provided at the center portion of each of the sides, butthe protruding portion 22 may be provided at a position deviated fromthe center portion of each of the sides, or two or more protrudingportions 22 may be provided for one side (for example, refer to (D) ofFIG. 14 ). In addition, as shown in (A) to (E) of FIG. 13 , even whenthere is only one protruding portion 22, the radiation detection panel30 and the base substrate 20 can be easily carried by gripping theprotruding portion 22. That is, the handleability of the radiationdetection panel 30 and the base substrate 20 is improved by the portionon which the protruding portion 22 is provided. On the other hand, whena plurality of protruding portions 22 are provided, the base substrate20 can be stably gripped at a plurality of locations, and thus thehandleability can be further improved.

Further, the protruding portion 22 may be provided on both the cornerportion and the side portion of the main body 21. That is, thearrangement of the protruding portions 22 shown in the above-describedembodiment and FIG. 13 and the like may be arbitrarily combined.

In the above-described embodiment, although the first extending portion81 (the first extending portion 81 in which the guide groove 81 a isprovided) as the positioning member is provided at a positioncorresponding to each of the four corners of the substrate 31, at leastone first extending portion 81 as the positioning member may beprovided. Also in this case, since it is possible to position two sidesadjacent to each other (two sides orthogonal to each other) with thecorner portion of the substrate 31 interposed therebetween, thesubstrate 31 can be positioned. However, as shown in (A) to (C) of FIG.14 , the first extending portion 81 as the positioning member ispreferably provided at positions corresponding to two or more cornerportions of the substrate 31. Thus, workability when the substrate 31 isdisposed on the support surface 20 a of the base substrate 20 can beimproved.

Further, as shown in (D) to (F) of FIG. 14 , when the protruding portion22 is provided on the side portion of the main body 21, the firstextending portion 81 may have a guide surface 81 c (a surface parallelto the side portion of the corresponding substrate 31 when seen in the Zdirection) for positioning the side portion of the substrate 31.Further, in this case, at least one (two in total) first extendingportion 81 may be provided on each of two sides orthogonal to eachother. However, as shown in (D) to (F) of FIG. 14 , preferably, thefirst extending portion 81 as the positioning member is provided atthree or more locations. Thus, workability when the substrate 31 isdisposed on the support surface 20 a of the base substrate 20 can beimproved.

Further, the first extending portion 81 as the positioning member may beprovided on both the corner portion and the side portion of the mainbody 21.

The first extending portion 81 used as the positioning member may beremoved after the substrate 31 is fixed to the support surface 20 a.However, it is possible to prevent occurrence of a handling mistake whenthe first extending portion 81 is removed, and thus it is possible toprevent damage to members such as the base substrate 20 due to thehandling mistake (that is, a decrease in a yield of the radiationimaging device 1) by leaving the first extending portion 81 even afterthe substrate 31 is fixed to the support surface 20 a. Further, thefirst extending portion 81 can serve as a protective member forprotecting the end portion of the substrate 31 (in the above-describedembodiment, the corner portion 31 d of the substrate 31) by leaving thefirst extending portion 81. Furthermore, as in the above-describedembodiment, the first extending portion 81 can be utilized as a supportmember for connecting the protruding portion 22 to the top wall 11.

In the above-described embodiment, although the first extending portion81 serves as the positioning member for positioning the substrate 31 andalso serves as the supporting member for supporting the protrudingportion 22 with respect to the top wall 11, the first extending portion81 may have only one function of the positioning member and thesupporting member. That is, the portion for positioning the substrate 31(the guide groove 81 a in the embodiment) may not be provided in thefirst extending portion 81. Alternatively, the first extending portion81 may not be fixed to the top wall 11. Alternatively, the firstextending portion 81 may be omitted. Further, when the plurality ofprotruding portions 22 are provided, the first extending portion 81 maybe provided only on any of the protruding portions 22. Similarly, thesecond extending portion 82 may be omitted. Further, when the pluralityof protruding portions 22 are provided, the second extending portion 82may be provided only on any of the protruding portions 22.

The protruding portion 22 may be omitted. That is, the base substrate 20may be a member consisting only of the above-described main body 21. Inthis case, the first extending portion 81 and the second extendingportion 82 fixed to the protruding portion 22 may also be omitted.

In the above-described embodiment, although the base substrate 20 isformed not to overlap all the connection regions A when seen in the Zdirection, the base substrate 20 may be formed not to overlap at leastone connection region A, and may not necessarily be formed not tooverlap all the connection regions A. For example, the base substrate 20may be formed not to overlap the connection region A corresponding tothe flexible circuit substrate 40 on which the IC chip 42 having aparticularly high failure rate (that is, repair work is likely to occur)is mounted but to overlap other connection regions A. In this case,although the procedure shown in the above-described embodiment (that is,the procedure of connecting each of the flexible circuit substrates 40to each of the electrode pads 33 after the radiation detection panel 30is supported on the base substrate 20) cannot be performed, theradiation imaging device 1 can be manufactured by connecting each of theflexible circuit substrates 40 to the radiation detection panel 30 andthen supporting the radiation detection panel 30 on the base substrate20. Further, when the IC chip 42 breaks down due to the base substrate20 being formed not to overlap the connection region A corresponding tothe flexible circuit substrate 40 on which the IC chip 42 having a highfailure rate is mounted, the repair work of the flexible circuitsubstrate 40 can be performed without removing the radiation detectionpanel 30 from the base substrate 20. Therefore, even when the basesubstrate 20 is formed not to overlap only a part of the connectionregion A in this way, similar to the above-described embodiment, therepair work of the flexible circuit substrate 40 corresponding to theconnection region A can be easily performed, and the effect of curbingnoise in the signal transmitted via the flexible circuit substrate 40 isachieved.

In the above-described embodiment, although only the flexible circuitsubstrate 40 is used as an electrical connection means with each of theelectrode pad 33, a connection means other than the flexible circuitsubstrate 40 (for example, wire bonding or the like) may be used incombination. For example, any of the electrode pads 33 may be connectedto the control substrate 50 via the flexible circuit substrate 40, andother electrode pads 33 may be connected to the control substrate 50 (ora control circuit provided separately) by wire bonding.

Also, in the above-described embodiment, although the external IC chip42 and the electrode pad 33 are electrically connected via the flexiblecircuit substrate 40, for example, a substrate for mounting a chip maybe accommodated in the housing 10, and the IC chip may be mounted on thesubstrate. Further, the IC chip and the electrode pad 33 may beelectrically connected only by a connecting means other than theflexible circuit substrate 40 (for example, the above-described wirebonding). Further, in such a case, since the connection region A asdescribed in the above-described embodiment is not present, the endportion 21 a of the base substrate 20 may not be disposed further inwardthan the end portion 31 c of the radiation detection panel 30 (thesubstrate 31) when seen in the Z direction. That is, the base substrate20 having a size which completely includes the substrate 31 when seen inthe Z direction (that is, the base substrate 20 of which the entireperipheral edge portion is located further outward than the substrate 31when seen in the Z direction) may be used. In this case, the entireperipheral edge portion of the base substrate 20 corresponds to theprotruding portion 22 in the above-described embodiment.

Also, in the above-described embodiment, from the viewpoint ofpreventing interference between the base substrate 20 and the flexiblecircuit substrate 40 and reducing the proportion of the dead region, theend portion 21 a of the base substrate 20 corresponding to the portionto which the flexible circuit substrate 40 is connected may be locatedfurther inward than the end portion 31 c of the radiation detectionpanel 30 (the substrate 31), and the base substrate 20 may not be formednot to overlap the connection region A when seen in the Z direction.

In the above-described embodiment, although the detection region R is aregion to which an indirect conversion method in which a radiation imageis converted into an optical image by the scintillator 34 and then thelight image is imaged by the light receiving part 32 to obtain an imageis applied, the detection region R may be a region to which a directconversion method for directly capturing the radiation image to obtainan image is applied. For example, on the first surface 31 a of thesubstrate 31, a pixel circuit configured to accumulate and transferelectric charges may be provided instead of the light receiving part 32,and a solid material (a converting part) (for example, CdTe, CdZnTe,GaAs, InP, TlBr, HgI2, PbI2, Si, Ge, a-Se, or the like) which directlyconverts radiation into electric charges may be provided instead of thescintillator 34. Thus, the detection region R to which the directconversion method is applied is obtained. In this case, the detectionregion R is a region on which radiation is incident and is a region towhich a bias voltage is applied (that is, a region for which an image isacquired). Since such a solid material also has a property that it issensitive to a high temperature like the scintillator 34, preferably, adistance between the solid material and the connection region A (thatis, the distance d between the end portion 21 a of the base substrate 20and the inner end portion A1 of the connection region A) is as large aspossible. Specifically, even when the solid material is provided (in thedirect conversion method), the distance d is preferably set to 1 mm ormore, as in the case in which the scintillator 34 is provided (in theindirect conversion method). Thus, a certain distance (at least 1 mm ormore) can be secured between the heater H1 which heats the connectingmember 70 to connect the flexible circuit substrate 40 to the electrodepad 33 and the solid material. As a result, an adverse effect of theheat from the heater H1 on the solid material can be curbed.

In the above-described embodiment, although the radiation detectionpanel 30 in which polycrystalline silicon, amorphous silicon, or thelike is formed on the substrate 31 which is a glass substrate has beendescribed, the radiation detection panel 30 is not limited to theabove-described configuration, and may have a configuration in which thelight receiving part is formed on, for example, a single crystal siliconsubstrate. Further, the substrate 31 is not limited to the glasssubstrate, and may be, for example, a film-shaped substrate (a flexiblesubstrate) or the like.

REFERENCE SIGNS LIST

-   -   1 Radiation imaging device    -   10 Housing    -   11 Top wall (first wall portion)    -   12 Bottom wall (second wall portion)    -   13 Side wall (third wall portion)    -   13 c Recess    -   20 Base substrate    -   20 a Support surface    -   20 b Back surface    -   21 a End portion    -   22 Protruding portion    -   30 Radiation detection panel    -   31 c End portion    -   32 Light receiving part    -   33 Electrode pad    -   34 Scintillator (conversion part)    -   40 Flexible circuit substrate    -   70 Connecting member    -   81 First extending portion    -   82 Second extending portion    -   112 Shield member    -   A Connection region    -   A1 Inner end portion    -   H1 Heater (first heater)    -   H2 Heater (second heater)

The invention claimed is:
 1. A radiation imaging device comprising: a radiation detection panel having a first surface on which a detection region for detecting radiation is formed and a second surface on a side opposite to the first surface; a base substrate having a support surface configured to face the second surface of the radiation detection panel and configured to support the radiation detection panel; and a housing configured to accommodate the radiation detection panel and the base substrate, wherein the housing has a first wall portion which faces the first surface and a second wall portion which faces the second surface, the base substrate has a protruding portion which protrudes further outward in a second direction parallel to the support surface than the radiation detection panel when seen in a first direction orthogonal to the support surface, a first extending portion configured to extend in the first direction is provided on the support surface of the protruding portion, a second extending portion disposed at a position at which the second extending portion faces the first extending portion with the protruding portion interposed therebetween and configured to extend in the first direction is provided on a surface of the protruding portion on a side opposite to the support surface, and the base substrate is supported on the first wall portion via the first extending portion and is supported on the second wall portion via the second extending portion.
 2. The radiation imaging device according to claim 1, wherein the first extending portion is a positioning member which positions the radiation detection panel.
 3. The radiation imaging device according to claim 1, wherein the first extending portion and the second extending portion are formed separately from the base substrate.
 4. The radiation imaging device according to claim 1, wherein the first extending portion and the second extending portion are mounted on the protruding portion by a common mounting member.
 5. The radiation imaging device according to claim 1, wherein: the second extending portion is larger than the first extending portion when seen in the first direction, and the second extending portion has a portion which does not overlap the first extending portion when seen in the first direction.
 6. The radiation imaging device according to claim 1, wherein a plurality of first extending portions disposed apart from each other are provided, and a plurality of second extending portions disposed apart from each other to correspond to the plurality of first extending portions are provided on the support surface of the protruding portion.
 7. The radiation imaging device according to claim 6, wherein: the base substrate has a plurality of protruding portions disposed apart from each other, and the first extending portion and the second extending portion are provided on each of the plurality of protruding portions.
 8. The radiation imaging device according to claim 7, wherein: the radiation detection panel is formed in a rectangular shape when seen in the first direction, and the plurality of protruding portions are provided at positions corresponding to four corners of the radiation detection panel.
 9. The radiation imaging device according to claim 8, wherein: the housing has a third wall portion which extends in the first direction and connects the first wall portion to the second wall portion, the third wall portion is formed in a rectangular ring shape when seen in the first direction, a recess which avoids interference with the protruding portion, the first extending portion, and the second extending portion is formed in each corner portion of the third wall portion, and a thickness of the third wall portion in the recess is smaller than a thickness of the third wall portion on a side portion of the third wall portion which connects the adjacent corner portions of the third wall portion.
 10. The radiation imaging device according to claim 9, wherein: the first wall portion has a shield member which is disposed to be in surface contact with the third wall portion and shields electromagnetic waves, and the first wall portion is screwed to the side portion of the third wall portion and the first extending portion. 